Plug cap



Dec. 24, 1935.

B. J. YANCHENKO 7 2,025,189

PLUG CAP Filed July 2, 1932 2 Sheets-Sheet l a" v INVENTOR Bag! jam/01196 FH'aS.

Patented Dec. 24, 1935 PLUG CAP-

Basil J. Yanchenko, New York, N. Y., assignor to Hatfield Wire & poration of New Jersey Cable (30., Hillside, N. J., a cor- Application July 2, 1932, Serial No. 620,558

3 Claims.

This invention relates to flexible wire end connections and more particularly to portable resilient plug caps for separable plug connectors used in connection with electrical appliance wires, cords and the like.

An object of the invention is to produce several simplified forms of novel unbreakable, resilient and weather proof plug caps comprising a one-piece molded construction together with contact prong means carried therewith and anchorage means to secure the parts together. In this connection, it is an object to produce plug caps having a simple anchorage pin or shoulder means to hold the parts together and which is characterized by low manufacturing cost.

Another object is to produce a novel one-piece molded resilient or rubber plug cap which can be quickly assembled with the contact prongs and electrical conductor cord and which requires no screws, pins or other securing means to anchor these parts within the molded resilient body member. I

Changes in construction may be made without departing from the principles of the invention, and the accompanying drawings are presented to show a variety of structural examples or concrete forms thereof by which the comprehensiveness of the invention is more fully appreciated.

Figures 1 thru show one form of the inven tion having a novel form of flexible or yielding anchorage pin made of insulation material to secure the parts together.

Figure 1 shows a longitudinal section of the first form of the molded plug cap assembled or connected with a flexible wire or electrical appliance cord.

Figure 2 shows a longitudinal section of the plug cap body with the conductor cord and contact prongs removed therefrom.

Figure 3 shows the manner of preparing the ends of the conductor cord or flexible wires, with the electrical contact prongs soldered thereto, before inserting the same in the plug cap body of Figure 2.

Figure 4 shows an outside elevation of the complete rubber plug cap assembly attached to an electrical appliance cord and ready for use.

Figure 5 shows an end or face view of the completed plug cap of Figure 4.

Figures 6 thru show a modified form. of the invention characterized by a somewhat different anchorage means to secure the parts together and in which the pin may be omitted to reduce the number of parts and to also shorten the time required to assemble the device.

Figure 6 shows a longitudinal section of the molded rubber plug cap with the flexible wire conductor cord and contact prongs removed therefrom.

Figure 7 shows a view similar to Figure 6 but 5 the contact prongs and flexible wire conductor are assembled in the cap.

Figure 8 shows the manner of drawing the contact prongs with their attached wires into the flexible plug cap. It is noted that a special as- 10 sembling tool may be used to facilitate this operation.

Figure 9 shows the contact prongs soldered to the wires to prepare these parts preliminary to drawing them into the plug body as illustrated in Figure 8.

Figure 10 is a cross section on the line I 0-l0 of Figure 7 showing the double thickness end of each contact prong which interlocks behind a cooperating shoulder to secure the parts together.

The plug cap comprises a soft or resilient body or head I which may be molded of rubber and having a long tapering flexible neck 8 to receive an appliance cord or wire W of the usual form. The tube or neck 8 includes a wire passage 9 which leads toward the round head or body I and the passage 9 divides into two spaced passages lll which lead out through the base or end of the plug body l. The member I, 8 is preferably made of rubber or the like and is molded integrally in the form shown. It is, therefore, unbreakage, is resilient, withstands hard use, and is silent when dropped or dragged on the floor.

The two passages ill are divided or set off by a wedge shaped guiding rib or partition H2 integral with the head i and neck 8. This wedge 12 has its pointed end directed centrally toward the tubular passage 9 of the flexible neck 8 and its thick end forms part of the end face of the head I. The two spaced passage means III are, therefore, tapered in conformity with the central wedge andincrease in narrowness to-- ward the large end of the integral wedge l2. This construction, therefore, terminates the two passages H1 in spaced and parallel restricted grooves M which produces a tight wall fit around and against electrical contact prongs, as later described. The enlarged taper ing ends of the passages l0, adjacent the neck 8, are wide open and afford an easy receiving opening by which the contact prongs are slid into position, as shown in Figure 1, by inserting the Wire W from the open end of the neck 8.

The head'portion l of the flexible or rubber plug cap is provided with a transverse hole I6 formed therethrough and this aperture is shown placed adjacent the end face of the enlarged head 1. This opening I6 is formed diametrically and centrally through the head 1 and passes through the dividing rib l2 and through the passages ||l near their reduced extremities I4.

The conductor wire W has its ends |8 cleaned of insulation to bare its copper terminals |8 and the latter are soldered to the rear extremities and on the adjacent surfaces of the two metal contact prongs H! to produce the construction such as rawhide or leather, is passed through,

the hole i6 and through corresponding apertures 2| formed in the contact prongs |9 to anchor the latter in position within the passages l4. The pin 20 and narrow passages |4 securely hold the contact means H3 in spaced relation with the wedge |2 as a dividing wall disposed therebetween. The pin 29 is sufiiciently flexible to affor-d relative movement between'the prongs l9 and thus enable said prongs to make positive electrical connection with an outlet plug receptacle into which the plug cap 1 is adapted to be inserted. Thus is produced a durable terminal end on the cord or wire W for all manner of service in connection with electrical appliances. The rubber neck 8 frictionally grips the cord W and thus takes some of the strain off of the soldered connections l8. It is noted that the metallic contact prongs l9 may be made considerably longer than shown so as to increase the soldered length and area for securing the bare wire ends l8 to the electrical contacts l9.

A description will now be given of the second form of the invention as shown in Figures 6 thru 10, illustrating a modified and preferred form of the invention, and having an improved means for securely anchoring the contact prongs and conductor cord within the moulded plug cap body.

In this type of construction, the molded body comprises a one-piece member made of rubber or the like and including a head or body 25 integrally formed with a flexible neck or tubular extension 26. This molded part possesses an internal shoulder which forms an interlock to hold the parts together after assembled, as will be described. The neck has its passage 21 enlarged within the head 25 and divided by an integral and irremovable wedge and partition means 28.

This construction forms narrow openings 29 leading out through the face of the head 25 and spaced apart the correct distance to receive contact prongs, as will be explained.

Each narrow passage 29 connects through an angular passage 30 with the neck or opening 21 which receives the conductor cord W. In other words, the passages 29 for the contacts converge at 30 and join the tubular passage 21. Internal shoulder means are formed at 3| at the juncture of the angular passages 29 and 30. The resilient material, say rubber, at the shoulders 3 I, as well as in the pointed wedging means 32 or dividing wall 28, yields or compresses to receive the contact prongs as the latter are drawn through the plug cap and into place, as will be explained.

The integral dividing partition or wedge like center part 28 is reduced in size, and may be pointed or made wedge-shaped at 32 and centrally located within or directed toward the passage 21. The wedging end or point 32 serves to guide the contact prongs into final position as will be explained. Furthermore, the integral center means 28 is grooved out so to speak at 34 on each side thereof within the passages 29 and has a stop end shoulder 33 at the upper end of each groove. By referring to Figure '7, it will be observed that the grooves 34 with shoulders 3| and 33, cooperate to produce a compressible wedging interlock for positively retaining the contact prongs against endwise displacement in the head 25 of the plug cap. A flexible conductor cord 'W having the usual pair of circuit wires is freed of insulation to expose its bare ends 36 and the latter are soldered to a folded back extremity 31 formed on each end of each contact prong 38 of the pair. The plug-in prongs or contact blades are of the usual shape and size at their outer ends. It is noted that the contact prongs '38 are first made substantially long whereupon their extremities 31 are doubled back upon the contact plate or prong portion 38 and this construction affords a thick extremity or end surface 39 on each contact adjacent the bare wires 36. When the member 31, 38 is doubled upon itself, there is produced the arcuate or rounded should-er extremity at 39 which is the counterpart of the shoulder 3| in the molded body 25. This completes the subassembly shown in Figure 9 which is now ready to be drawn into the molded member 25.

By reference to Figure 8, the method of-com- 4o plating, the plug cap is readily understood. There is provided an assembling tool in the form of a fork having long flexible prongs or tines 4| with a hook 42 directed outwardly on the extremity of each tine. on an eye or handle 43 which a workman grasps in handling the device. The tool is flexible and is easily thrust through the molded body 25, as shown in Figure 8, until the hooks 42 are exposed at the free end of therubber neck 26.. The hooks 42 are set on the inside of the contact pron-gs 38 and inserted outwardly through the perforation ordinarily provided at the outer end of each contact prong of an electric plug cap.

The workman now grasps the rubber plug 25 with one hand and the assembling tool 43 with the other, and draws the contact prongs 38 and attached wire cord W through the neck 26 and into the plug 25. The resilient material forming the plug yields or stretches to permit the thick metallic ends 31 to pass the shoulders 3| whereupon the compressible body expands back to original position behind the ends 39 of the contact prongs and the latter are locked in place. Likewise the flat upper ends of the bent portions 5 31, opposite the rear shouldering lower ends 39, abut against the inner face of the partition 28 at the closed ends of the grooves 34. The folded over ends 31 now lie fixed within the grooves 34.

The contact prong 31, 38 is the counterpart of The tines 4| are carried 45 the grooves 34 fix the contact prongs against being pulled outwardly by the assembling tool 43 and the shoulders 3! and 39 fix the contact prongs against rearward displacement. The double thickness portion at 31 abuts with the ends 33 of the grooves 34 and against the shoulder 3| after the latter snap or expand closed behind the metallic ends 39 when drawn into final position by the tool 43. The compressibility of the rubber body yields to admit the metallic parts and thereafter expands and tightly squeezes the contact prongs and the appliance cord W in, place, thereby anchoring all parts together.

The foregoing construction produces a plug cap of relatively few parts and without employing any pin or screw fastening means. The contact prongs 38 move relatively one to the other if need be when thrusting same into the slots of the usual plug-in receptacle. The neck 26 frictionally grips the cord W and thus carries much of the strain when pulling on the cord W to jerk the plug cap 25 out of its plug-in socket receptacle.

It is noted that the bare wires 36 have a substantially long soldered length and can, therefore, be securely anchored to the ends of the prongs 38. In fact, the folded extremities 31 may be increased in length and the body grooves 34 made longer by which to increase the soldering area and length when attaching the bare wires 36 to the metal prongs 38.

In both forms of construction, the contact prongs have their rear or inner extremities attached or secured to the two circuit wires forming the flexible conductor W. Thus the entire remaining portions of the contact prongs are gripped by the walls forming the passages through the head of the plug cap. The axial opening through the necks of my plug caps are enlarged somewhat in the head portion and the partition wedge is located centrally therein. In this way the contact prong receiving openings branch out or diverge to either side of the integral wedge means or dividing wall indicated at l2 and 28 which eiTectively braces and insulates the contact prongs in service position.

This invention affords a durable and moisture proof plug cap in both of its forms, withstands hard usage, cannot break or chip when subjected to hard service, and is noiseless in use if droppedor dragged on the floor.

What is claimed is:

1. A plug cap comprising a one-piece member molded of flexible material and having an opening at one end adapted to receive a conductor having circuit wires, said opening having diverging passages spaced apart and leading through the member, an integral dividing partition wall 5 disposed between the passages and reducing the size of the latter in relation to the opening, said partition wall having a wedge-shaped extremity disposed centrally in the diverging passages and adapted to separate circuit wires leading in 0 through the opening, a contact prong mounted in each passage and having its inner end placed adjacent the diverging passages, and a removable flexible pin of insulation material disposed through the member and through both contact 15 prongs.

2. A plug cap comprising a resilient body member including a head anda neck integral therewith, said head and neck being provided with a passage formed throughout the length thereof, a 20 wedge-shaped partition means in the passage and integrally formed with the head and having its pointed or wedge-shaped end directed toward the neck, said integral partition serving to divide the passage in the head into two spaced reduced size 25 openings, a contact prong placed in each opening and projecting from the head, a conductor disposed in the neck and having two wires divided and insulated by the integral partition and attached to each contact prong, and a remov- 30 able pin inserted through an aperture formed diametrically through the head and through the contact prongs to secure all parts together.

3. A plug cap comprising a member molded of rubber and provided with a pair of spaced pas- 35 sages opening out through the face thereof, said passages converging rearwardly into one large opening adapted to receive a conductor cord, the spaced passages being divided off by an integral partition wall having a wedge-shaped end di- 40 rected toward the one large opening, a contact prong mounted in each spaced passage and each inner end of said contact prong extending rearwardly toward the wedge-shaped end of the partition wall, and a removable pin inserted through 45 the molded member transversely to the passages and through the contact prongs to hold all parts together, said pin being formed of a flexible insulating material to afiord relative motion between the contact prongs and within the rubber 50 member.

BASIL J. YANCHENKO. 

